1. Field
The present invention relates to a method and system for a multi-stage inflation of a curtain airbag for ejection mitigation.
2. Description of the Related Art
A conventional automobile may include a curtain airbag which can be inflated during a side impact or a rollover. The inflation of the curtain airbag is designed to reduce a likelihood of injury to the user of the automobile, such as to reduce the likelihood that the user will be ejected from the automobile, and/or to reduce the likelihood that the user will impact a hard object. To inflate the curtain airbag, the conventional automobile can use a conventional cold gas inflation unit. During a side impact or a rollover, the conventional cold gas inflation unit can inflate the curtain airbag by deploying compressed air from a canister. However, such canisters are often heavy and expensive, which can reduce efficiencies of the automobile and also increase the manufacturing costs of the automobile.
In addition, government agencies may require that the curtain airbag be inflated at a certain pressure at certain time periods. However, with the conventional cold gas inflation unit, the pressure in the curtain airbag increases to a climax and then slowly decreases. This may provide inadequate pressure to meet the requirements of the governmental agencies.
A conventional pyrotechnic inflation unit has also been used for airbags, since it is generally lighter and has a reduced cost. However, a conventional pyrotechnic inflation unit is also inadequate because it may provide a quick burst of pressure, but it does not adequately maintain the pressure of the curtain airbag by itself. The inflation of the curtain airbag using the pyrotechnic inflation unit, therefore, may be unable to meet the requirements of the governmental agencies.
Thus, there is a need for a method and system for a multi-stage inflation of a curtain airbag for ejection mitigation.